ImmunoGen, Inc. Announces Clinical Data Presentations at the 54th ASH Annual Meeting and Exposition

ImmunoGen, Inc. (NASDAQ: IMGN), a biotechnology company that develops anticancer therapeutics using its Targeted Antibody Payload (TAP) technology and antibody expertise, today announced that there will be clinical data presentations on two compounds that utilize the Company’s TAP technology at the 54th annual meeting of the American Society of Hematology (ASH) to be held December 8-11, 2012 in Atlanta, GA.

“With ten TAP compounds now in clinical testing – and more in development behind these – we expect an increasing amount of clinical data to be reported on TAP compounds for the foreseeable future,” commented Daniel Junius, President and CEO. “At this year’s annual meeting of ASH, clinical findings will be reported with both our IMGN901 compound and Biotest’s BT-062 compound. Over the course of 2013, we expect data presentations with TAP compounds for the treatment of a number of types of solid tumors as well as additional data to be reported for hematological malignancies.”

IMGN901 Oral Presentation

• Title: “Phase I Study of Lorvotuzumab Mertansine (LM, IMGN901) In Combination with Lenalidomide (Len) and Dexamethasone (Dex) In Patients with CD56-Positive Relapsed or Relapsed/Refractory Multiple Myeloma (MM)” (Abstract #728).
• When/where: Dec. 10 at 4:45 pm ET in the Thomas Murphy Ballroom 2-3 (Session #653).

BT-062 Poster Presentation

• Title: “BT062, An Antibody-Drug Conjugate Directed Against CD138, Given Weekly for 3 Weeks in Each 4 Week Cycle: Safety and Further Evidence of Clinical Activity” (Abstract #4042).
• When/where: Dec. 10 from 6:00-8:00 pm ET in Hall B1-B2 (Session #653; Poster III).

About IMGN901

IMGN901 is wholly owned by ImmunoGen and consists of the Company's CD56-targeting lorvotuzumab antibody with its DM1 cancer-cell killing agent attached using one of its engineered linkers.

IMGN901 is in Phase II testing, in the NORTH trial, for the first-line treatment of extensive disease small-cell lung cancer (SCLC). Encouraging findings also have been seen in initial evaluations of the compound for the treatment of multiple myeloma and Merkel cell carcinoma (MCC). IMGN901 has been granted orphan drug designation for SCLC, multiple myeloma and MCC in the US and Europe.

About ImmunoGen, Inc.

ImmunoGen, Inc. develops targeted anticancer therapeutics using its TAP technology together with the Company’s expertise in monoclonal antibodies and tumor biology. A TAP compound uses a tumor-targeting monoclonal antibody to deliver one of ImmunoGen's purpose-developed cancer-killing agents specifically to tumor cells. Ten TAP compounds are now in clinical testing, of which three are wholly owned by the Company. Marketing applications for trastuzumab emtansine (T-DM1), the most advanced compound using ImmunoGen's TAP technology, are under review in the US and Europe. Roche is developing this compound globally under an agreement between ImmunoGen and Genentech, a member of the Roche Group. More information about ImmunoGen can be found at www.immunogen.com.

This press release includes forward-looking statements. For these statements, ImmunoGen claims the protection of the safe harbor for forward-looking statements provided by the Private Securities Litigation Reform Act of 1995. It should be noted that there are risks and uncertainties related to the development of novel anticancer products, including risks related to preclinical and clinical studies, their timings and results. A review of these risks can be found in ImmunoGen’s Annual Report on Form 10-K for the fiscal year ended June 30, 2012 and other reports filed with the Securities and Exchange Commission.